Creating Textures with feTurbulence

Creating noise, marble, or cloud effects across an image requires using the feTurbulence primitive. feTurbulence creates a texture-like pattern on an object using a variety of custom properties.

Somewhat oddly, feTurbulence has two different functions (specified by the type attribute): turbulence and noise. The turbulence value creates soft, bubble-like patterns that appear as prismatic clouds, whereas fractalNoise creates a randomized dot texture, similar to gravel or snow being tossed across the image.